Question 158: EM waves

Question

An electromagnetic wave of frequency $$v=3.0$$ $$MHz$$ passes from vacuum into a dielectric medium with permittivity $$ \in  = 4.0.$$ Then

Accepted Answer

Frequency remains constant during refraction
$${v_{med}} = {1 \over {\sqrt {{\mu _0}{ \in _0} 	imes 4} }} = {c \over 2}$$
$${{{\lambda _{med}}} \over {{\lambda _{air}}}} = {{{v_{med}}} \over {{v_{air}}}} = {{c/2} \over c} = {1 \over 2}$$
$$	herefore$$ wavelength is halved and frequency  remains unchanged

Answer

wave length is halved and frequency remains unchanged

Answer

wave length is doubled and the frequency becomes half

Answer

wave length is doubled and the frequency remains unchanged

Answer

wave length and frequency both remain unchanged.

EM waves

An electromagnetic wave of frequency $v=3.0 MHz passes from vacuum into a dielectric medium with permittivity \in = 4.0.$ Then

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